From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-19.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AE2B4C4332E for ; Wed, 6 Jan 2021 17:18:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6C232221EA for ; Wed, 6 Jan 2021 17:18:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727801AbhAFRRz (ORCPT ); Wed, 6 Jan 2021 12:17:55 -0500 Received: from mail.kernel.org ([198.145.29.99]:60416 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727693AbhAFRRy (ORCPT ); Wed, 6 Jan 2021 12:17:54 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id EE4A723137; Wed, 6 Jan 2021 17:17:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1609953433; bh=dJKB1Seld/aPWAIbVyEarvxi8yJh2NGngiS29t6dWN8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bwmRuq57zaBJOcQUf+dPZJ3e+bvw153GpMQoZFFkm2P2jddVHhTDJqGYImdyuVf9y CBJ/Zt/yztzYQdyqinYN7R223bvMqZvUaKbmDYKiYxzsY5ynEbK3UeU7HUGJ/peAr1 7YxM+z0k3LZumZELQ5id5T7jSrAh6BbYdmBNoWiXvQ8y6t56Bn5PiUcHvQ7rUFz7O0 zAR3rBY+xVia4JIRuyiL22k/VMj1zjaavIzqyH9z9lpCywVdfuEmYWSvcllF5T4y/4 L+7P6EyyMh+33V66gfP4wIDNvdBxMlYbtFKh+/4c8NwbSI/7Ok6xm1D2+TQ90H6FiT 2BqIc0Iuuu3uQ== From: paulmck@kernel.org To: rcu@vger.kernel.org Cc: linux-kernel@vger.kernel.org, kernel-team@fb.com, mingo@kernel.org, jiangshanlai@gmail.com, akpm@linux-foundation.org, mathieu.desnoyers@efficios.com, josh@joshtriplett.org, tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org, dhowells@redhat.com, edumazet@google.com, fweisbec@gmail.com, oleg@redhat.com, joel@joelfernandes.org, "Paul E. McKenney" Subject: [PATCH tip/core/rcu 05/17] rcutorture: Make synctype[] and nsynctype be static global Date: Wed, 6 Jan 2021 09:16:58 -0800 Message-Id: <20210106171710.22239-5-paulmck@kernel.org> X-Mailer: git-send-email 2.9.5 In-Reply-To: <20210106171532.GA20769@paulmck-ThinkPad-P72> References: <20210106171532.GA20769@paulmck-ThinkPad-P72> Precedence: bulk List-ID: X-Mailing-List: rcu@vger.kernel.org From: "Paul E. McKenney" Full testing of the new SRCU polling API requires that the fake writers also use it in order to test concurrent calls to all of the API members, especially start_poll_synchronize_srcu(). This commit prepares the ground for this by making the synctype[] and nsynctype variables be static globals so that the rcu_torture_fakewriter() function can access them. Initialization of these variables is moved from rcu_torture_writer() to a new rcu_torture_write_types() function that is invoked from rcu_torture_init() just before the first writer kthread is spawned. Link: https://lore.kernel.org/rcu/20201112201547.GF3365678@moria.home.lan/ Reported-by: Kent Overstreet Signed-off-by: Paul E. McKenney --- kernel/rcu/rcutorture.c | 62 ++++++++++++++++++++++++++++--------------------- 1 file changed, 36 insertions(+), 26 deletions(-) diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c index 1930d92..ea44a2b 100644 --- a/kernel/rcu/rcutorture.c +++ b/kernel/rcu/rcutorture.c @@ -1062,37 +1062,18 @@ rcu_torture_fqs(void *arg) return 0; } +// Used by writers to randomly choose from the available grace-period +// primitives. The only purpose of the initialization is to size the array. +static int synctype[] = { RTWS_DEF_FREE, RTWS_EXP_SYNC, RTWS_COND_GET, RTWS_POLL_GET, RTWS_SYNC }; +static int nsynctypes = 0; + /* - * RCU torture writer kthread. Repeatedly substitutes a new structure - * for that pointed to by rcu_torture_current, freeing the old structure - * after a series of grace periods (the "pipeline"). + * Determine which grace-period primitives are available. */ -static int -rcu_torture_writer(void *arg) +static void rcu_torture_write_types(void) { - bool boot_ended; - bool can_expedite = !rcu_gp_is_expedited() && !rcu_gp_is_normal(); - unsigned long cookie; - int expediting = 0; - unsigned long gp_snap; bool gp_cond1 = gp_cond, gp_exp1 = gp_exp, gp_normal1 = gp_normal; bool gp_poll1 = gp_poll, gp_sync1 = gp_sync; - int i; - int idx; - int oldnice = task_nice(current); - struct rcu_torture *rp; - struct rcu_torture *old_rp; - static DEFINE_TORTURE_RANDOM(rand); - bool stutter_waited; - int synctype[] = { RTWS_DEF_FREE, RTWS_EXP_SYNC, - RTWS_COND_GET, RTWS_POLL_GET, RTWS_SYNC }; - int nsynctypes = 0; - - VERBOSE_TOROUT_STRING("rcu_torture_writer task started"); - if (!can_expedite) - pr_alert("%s" TORTURE_FLAG - " GP expediting controlled from boot/sysfs for %s.\n", - torture_type, cur_ops->name); /* Initialize synctype[] array. If none set, take default. */ if (!gp_cond1 && !gp_exp1 && !gp_normal1 && !gp_poll1 && !gp_sync1) @@ -1127,6 +1108,34 @@ rcu_torture_writer(void *arg) } else if (gp_sync && !cur_ops->sync) { pr_alert("%s: gp_sync without primitives.\n", __func__); } +} + +/* + * RCU torture writer kthread. Repeatedly substitutes a new structure + * for that pointed to by rcu_torture_current, freeing the old structure + * after a series of grace periods (the "pipeline"). + */ +static int +rcu_torture_writer(void *arg) +{ + bool boot_ended; + bool can_expedite = !rcu_gp_is_expedited() && !rcu_gp_is_normal(); + unsigned long cookie; + int expediting = 0; + unsigned long gp_snap; + int i; + int idx; + int oldnice = task_nice(current); + struct rcu_torture *rp; + struct rcu_torture *old_rp; + static DEFINE_TORTURE_RANDOM(rand); + bool stutter_waited; + + VERBOSE_TOROUT_STRING("rcu_torture_writer task started"); + if (!can_expedite) + pr_alert("%s" TORTURE_FLAG + " GP expediting controlled from boot/sysfs for %s.\n", + torture_type, cur_ops->name); if (WARN_ONCE(nsynctypes == 0, "rcu_torture_writer: No update-side primitives.\n")) { /* @@ -2889,6 +2898,7 @@ rcu_torture_init(void) /* Start up the kthreads. */ + rcu_torture_write_types(); firsterr = torture_create_kthread(rcu_torture_writer, NULL, writer_task); if (firsterr) -- 2.9.5